Accepted Answer

I found a very simple fix to the "restart after sleep" problem on the Apple user forum. My white 13inch Macbook 2 GHz Intel Core 2 Duo, Leopard 10.5.8 . would display a message something like, "A kernel panic has occurred and the only thing you can do is hold down the power button until the machine shut off." ( paraphrased). This occurred after sleep whether by lid closing or software command.

Here is what worked for me:

1. In System Preferences, open Network preferences.

2. Highlight "Ethernet" or "Built in Ethernet".

3. Click the Minus sign ( - ) (at the bottom of the window just above the unlocked lock icon) to delete the Ethernet configuration.

4. Click the Plus sign ( + ) (at the bottom of the window just above the lock icon) then select "Ethernet" from the menu that appears. Then click "CREATE". (a new Ethernet configuration is created in the left section of the window). Then click "APPLY" on the lower right side of the window. Close the window.

5. Sleep the computer by closing the lid. Then wake it up. Then sleep it again. Then wake it up again. Everything should now work fine.

This worked perfectly for me the last time this happened. The previous time it happened, my son reinstalled the operating system and apps for me, which worked, but was probably overkill.

I've had bad topcases that caused irregular behavior related to sleep mode and rebooting. If you have another topcase available to test it might be worthwhile. Also, Apple laptops go into sleep mode due to various magnets throughout making a connection with each other, and if those magnets in the screen and body of the computer are in the wrong place or are not present, this can also cause bizarre behavior (computer continually going into sleep mode and then waking up, etc.) Particularly there are two magnets in the screen frame I know of related to this, so if by chance your screen has been swapped out, it's possible a magnet is missing.

I'm going to try a recommended solution involving disabling Safe Sleep mode which a number of folks have pointed to as a possible culprit. There is an application that will do the job or you can disable in terminal mode. http://www.jinx.de/SmartSleep.html

To disable safe sleep, run the two following commands in Terminal:

$ sudo pmset -a hibernatemode 0

$ sudo nvram "use-nvramrc?"=false

When done, restart your computer. Now go delete the file /private var vm sleepimage" to free up some hard drive space. When you put your computer to sleep it, should happen in under five seconds; my MacBook now goes to sleep in two seconds.

Note that if you disable safe sleep, your computer will lose all contents of memory if it runs out of battery power, instead of going into hibernate mode. It just means that you'll lose any unsaved work, which is usually not a big deal, but it's worth mentioning.

how long is the computer asleep for? is it instant? usually an apple will restart automatically if there is a power failure. your computer could have a number of issues wrong with it. try putting it to sleep plugged in without the battery in it... see if it does it. also, try the usual... reset the PRAM by holding down +Option+P+R on reboot and hold it until the computer chimes, not once but three times. also, then when the computer is off, reset the firmware, by holding down the power button until the light flashes and the computer emits a long tone. If none of those issues fix it, you might have a problem with a dc board or logic board and need to get it replaced

Tried all of the above plus PRAM, firmware, and SMC resets and so far nothing helps. In fact, it's worse. Now it shuts down every time I put it to sleep. Never had this with any of my Apple laptops or desktops before.

Is it only when it sleeps by shutting the lid? Does it sleep ok when you choose Sleep from the Apple menu? How about if it's booted to an external drive? That will help rule out software and point you more toward hardware.

There was a MacBook sleep/wake issue, that was corrected by an OS update. I'm not 100% sure which models, but it would definitely be an idea to ensure all possible updates are installed on your machine.

If you would like more info on the update, let me know and I can research it for ya. I'll save that effort for now though.

My macbook would have to restart after every sleep once i upgraded to Mavericks. I stopped it by prior to sending it to sleep, unplugging both my power cable and my thunderbolt/hdmi display. With Both unplugged it will wake up just fine. I know this is anecdotal, but it's the only thing that worked vs a few fixes various forums recommended.

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